feat: add currency field in balance model and modify balanceview endp…

…oint to return balance with currency.

payments/migrations/0003_balance_currency.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.0.4 on 2024-11-04 17:59
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("payments", "0002_balance"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="balance",
+            name="currency",
+            field=models.CharField(
+                choices=[("GEL", "GEL"), ("USD", "USD"), ("EUR", "EUR")],
+                default="GEL",
+                max_length=3,
+            ),
+        ),
+    ]

payments/models/balance.py

@@ -3,11 +3,20 @@
 from django.db import models, transaction
 
 
+class CurrencyChoices(models.TextChoices):
+    GEL = "GEL", "GEL"
+    USD = "USD", "USD"
+    EUR = "EUR", "EUR"
+
+
 class Balance(models.Model):
     user = models.OneToOneField(
         settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="balance"
     )
     amount = models.DecimalField(max_digits=10, decimal_places=2, default=0.0)
+    currency = models.CharField(
+        max_length=3, choices=CurrencyChoices.choices, default=CurrencyChoices.GEL
+    )
 
     def add(self, amount):
         """Add money to the balance."""

payments/openapi/balance_openapi_examples.py

@@ -21,7 +21,7 @@ def balance_view_examples():
             "Response example (Balance Retrieved)",
             summary="Successful balance retrieval",
             description="This example demonstrates the successful response containing the user's balance.",
-            value={"balance": 100.00},
+            value={"balance": 100.00, "currency": "GEL"},
             response_only=True,
             status_codes=[200],
         ),

payments/views.py

@@ -235,7 +235,10 @@ def get(self, request, user_id):
             user=user, defaults={"amount": 0}
         )
 
-        return Response({"balance": balance.amount}, status=status.HTTP_200_OK)
+        return Response(
+            {"balance": balance.amount, "currency": balance.currency},
+            status=status.HTTP_200_OK,
+        )
 
 
 @extend_schema(